Field of the Invention
The present invention relates to an image forming apparatus.
Description of the Related Art
In recent years, one quality of an image (hereinafter referred to as image quality) of an image forming apparatus (hereinafter referred to as printer) that is spreading is color reproducibility (including color stability). For color reproducibility, differences in color not only within the same model, but also across different models, and from an image display apparatus or an image forming apparatus of a different format is a problem. Because color mapping between such devices is performed, there is software and colorimeters for generating a multi-dimensional LUT called an ICC (International Color Consortium) profile, for example.
For example, a pro user generates an ICC profile of a printer and an ICC profile of an offset printing device, and constructs a color management environment as in FIG. 7. As illustrated in FIG. 7, the content of the ICC profile for printing and the ICC profile for the printer is that each is calibrated in association with a color space, on which the device does not depend, based on a color measurement of a patch using a colorimeter. A CIE L*a*b* color space (CIE is an international illumination commission; abbreviation of Commission Internationale d'Eclairage), for example, is an example of a color space that is not device dependent. By this, it is possible to cause colors printed on printing devices and colors printed by printers to match. Also, a color management module (CMM) is able to generate print data by performing color conversion using such profiles.
However, for color management environments as above, it takes effort to construct an environment, and the like, and so there has not been sufficient spread to general users. For this reason, it is desirable to speed up measurement, simplify generation of profiles, and automate setting work.
For example, in US2014/0226192, in color management using a color sensor, a method in which it is possible to reduce a number of sheets while suppressing an increase in the size of an image for measurement (a test chart) is disclosed.
In recent years, there is a strong desire for speed increases and elimination of user stress, and there is a rising need to improve a sheet conveying speed of an image forming apparatus and to shorten the time for calibration. Furthermore, demand is emerging that as few printing mediums as possible be required for calibration. At the same time, there is a strengthening desire for improving precision of calibration.